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Lib/test/test_os/test_dirfd.py

@@ -2,12 +2,12 @@
 Tests for the posix *at functions.
 """
 
-import posix
+import errno
 import os
-import unittest
-import time
+import posix
 import stat
-import errno
+import time
+import unittest
 from contextlib import contextmanager
 from test import support
 from test.support import os_helper

Lib/test/test_os/test_encoding.py

@@ -1,3 +1,7 @@
+"""
+Test encodings: filename encoding, os.fsencode(), device_encoding(), etc.
+"""
+
 import codecs
 import locale
 import os

Lib/test/test_os/test_environ.py

@@ -1,3 +1,7 @@
+"""
+Test the environment: os.environ, putenv(), etc.
+"""
+
 import os
 import posix
 import subprocess

Lib/test/test_os/test_fd.py

@@ -1,3 +1,7 @@
+"""
+Test file descriptors: pipe(), set_blocking(), memfd_create(), eventfd, etc.
+"""
+
 import errno
 import itertools
 import os

Lib/test/test_os/test_file.py

@@ -1,3 +1,7 @@
+"""
+Test files: open(), read(), pwritev(), truncate(), etc.
+"""
+
 import errno
 import os
 import posix

Lib/test/test_os/test_fspath.py

@@ -1,6 +1,6 @@
-import unittest
 import os
 import types
+import unittest
 from test.support.os_helper import FakePath
 
 

Lib/test/test_os/test_link.py

@@ -1,3 +1,7 @@
+"""
+Test symbolic and hard links: os.link(), os.symlink(), etc.
+"""
+
 import os
 import posix
 import shutil

Lib/test/test_os/test_macos_weaklink.py

@@ -1,7 +1,11 @@
-import unittest
+"""
+Test macOS weak linking.
+"""
+
 import os
-import sys
 import posix
+import sys
+import unittest
 from test.support import os_helper
 
 

Lib/test/test_os/test_process.py

@@ -1,6 +1,7 @@
 """
-Tests on processes: spawn(), exec(), fork(), waitpid(), etc.
+Tests processes: spawn(), exec(), fork(), waitpid(), etc.
 """
+
 import contextlib
 import errno
 import os

Lib/test/test_os/test_random.py

@@ -1,3 +1,7 @@
+"""
+Test random bytes: getrandom(), urandom(), etc.
+"""
+
 import errno
 import os
 import resource

Lib/test/test_os/test_scandir.py

@@ -1,3 +1,7 @@
+"""
+Test os.scandir() and os.DirEntry.
+"""
+
 import os
 import stat
 import sys

Lib/test/test_os/test_sendfile.py

@@ -1,9 +1,13 @@
-import socket
-import unittest
-import os
+"""
+Test os.sendfile().
+"""
+
+import asyncio
 import errno
+import os
+import socket
 import sys
-import asyncio
+import unittest
 from test.support import os_helper
 from test.support import socket_helper
 from .utils import create_file

Lib/test/test_os/test_stat.py

@@ -1,11 +1,15 @@
+"""
+Test os.stat(), os.fstat(), etc.
+"""
+
 import errno
 import os
+import pickle
 import posix
 import stat
-import unittest
-import pickle
-import sys
 import subprocess
+import sys
+import unittest
 from test.support import os_helper
 from .utils import create_file
 

Lib/test/test_os/test_terminal.py

@@ -1,13 +1,13 @@
 """
-Test the terminal: os.get_terminal_size(), os.openpty().
+Test the terminal: os.get_terminal_size(), os.openpty(), etc.
 """
 
+import errno
 import os
-import unittest
 import subprocess
-import errno
 import sys
 import textwrap
+import unittest
 from test import support
 from test.support import os_helper
 from test.support import warnings_helper

Lib/test/test_os/test_timerfd.py

@@ -1,3 +1,7 @@
+"""
+Test the timerfd API.
+"""
+
 import errno
 import os
 import select

Lib/test/test_os/test_user.py

@@ -1,3 +1,7 @@
+"""
+Test user functions: getuid(), setgid(), getgroups(), getlogin(), etc.
+"""
+
 import errno
 import os
 import posix

Lib/test/test_os/test_utime.py

@@ -1,3 +1,7 @@
+"""
+Test the os.utime() function.
+"""
+
 import decimal
 import fractions
 import os

Lib/test/test_os/test_windows.py

@@ -1,3 +1,7 @@
+"""
+Test Windows functions.
+"""
+
 import sys
 import unittest
 
@@ -14,11 +18,11 @@
 import textwrap
 import time
 import uuid
+import _winapi
 from test import support
 from test.support import import_helper
 from test.support import os_helper
 from .utils import create_file
-import _winapi
 
 
 class FileTests(unittest.TestCase):